Molarity is the amount of solute molecule (in moles) per 1L of solvent. In this case, the solute is 0.7mol Na2S and the solvent volume is 1.05L. Since the unit in this problem is already mol and L then you don't need to do any conversion of the units. The calculation would be:

molarity = mol of solute / (1L/ volume of solvent)
molarity = 0.7 mol/ (1L/ 1.05L)= 0.67M

6 0

3 years ago

A student mixes some water at room temperature with a white powder also at room temperature. The white powder disappears into th

Leya [2.2K]

Chemical change, because the white powder heated the water and caused a thermal reaction, and possibly gas was produced due to bubbles.

5 0

2 years ago

You are asked to weigh approximately 0. 4g of acetylsalicylic acid to the nearest mg. When you enter the data in grams in your l

krok68 [10]

Number of significant figures will be 1

Given:

weight of acetylsalicylic acid = 0. 4g

To Find:

significant figures

Solution: Significant figures are the digits of value which carry meaning towards the resolution of the measurement. They are also called significant figures in chemistry. All the experimental measurements have some kind of uncertainty associated with them.

When we convert 0.4g acetylsalicylic acid to mg we get value 400mg

when we convert 400mg to gram we get value of 0.4 gram

Since 0 before a decimal is not significant so there is only one significant figure that is 4

Learn more about Significant figure here:

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5 0

1 year ago